I-539 pending + Marriage question

Hello, I've been in the US for the past 4 years under an L1 A visa (with I94 till april/2020) working for a multinational. My job was terminated in July and I applied for a change of status to continue here and finish some trips and other things I had planned, as well as spending more time with my boyfriend of 6 months. The change of status was advised by my company as the L1 A visa would no longer be valid and I would be out of status. We have been talking about getting married so I would not have to leave and continue our journey together. Should we get married before the I539 change of status is determined ( it was filed end of June) and file the papers for the permanent status or should I leave the country after the I539 date and come back for the marriage purposes (we are not thinking about doing a K1 or Marriage visa due to the separation period) Thank you very much.